Self-contained breathing apparatus for use in noxious gases



A ril 6, 1926. 1,579,919

A. DRAGER SELF CONTAINED BREATHING APPARATUS FOR USE IN NOXIOUS GASES Filed June 9, 1921 2 Sheets-Sheet 1 April 6 1926. 1,579,919

" A. B. DRAGER SELF CONTAINED BREATHING APPARATUS FOR USE IN NOXIOUS GASES Filed June 1921 2 Sheets-Sheet 2 IVfll0M1lIIlIIIIIMIIlIIIIIIIlIIIfl/IIM lIIIlIl/IlIIIIIlllIllIIIIIIIIIIIIIIlllIIlIIIIll/III a 2 27 37 a as :5

Patented Apr.- 6, 1926.

UNITED- STATES PATE T o Frc-Ef- ALEXA DER BERNHARD nations, or LUBECK, GERMANY.

SELF-CONTAINED BREATHING APPARATUS non USE IN No xIoUs GAsEs.

Application filed June 9,

tained Breathing Apparatus for Use in' Noxious Gases, of which the following is a specification.

The invention relates to an apparatus for supplying respirable air to a person surrounded by irrespirableor poisonous gases or fumes, the. apparatus being adapted to be carried or worn packwise on the backand enabling the person to enter. and'to stay at places having an atmosphere which is nox lous.

a self-contained breathing apparatus arranged in the form of. a ,pack which, While preserving-a compact form, is'exceedingly simple in construction, 18 efliclent in use and fulfills all reasonable requir'ementsgin a betterand more reliable degree than-the known apparatus of the kind in question.

With this end in view the invention consists in certain novel features, combinations and arrangements of parts hereinafter fully described and particularly pointed out in the claims.

In the drawings: Figure 1 is a diagrammatic view of the apparatus spread or extended fiat on the ground. I

Fig. 1 is a detailed View of the'hinge connection of the valve chest shown in Fig. 1. Fig. 2 is an elevation on a larger scale of the pressure reducing valve and its high 1g. 1s a horizontal section 011 the line P-Q of Fig. 2. i

Fig. 4 is anelevation on an enlarged scale of a spring press-button valve. co'ntrollinga by-pass conduit between the high pressure oxygen supply pipe and a suitable part of pressure oxygen supply pipe.

- e air passage of the apparatus.

Fig. 5 is a vertical longitudinal section of the said spring press-button valve mechanism.

'Figs. 6 and 7'are sectional views illustrating the means whereby the free ends of the admitting and discharging branches of the bypass conduit are connected with the casing of the controlling press-button valve and -=the oxygen supply pipe'iand with thev ai'ix pasageof the apparatus.

valve chest c b 1921. Serial No. 476,238.

Similar letters and numerals refer to similar parts throughout the several views.

Referring to Figure 1 the improved selfcontained breathing apparatus comprises a mouthpiece m, a flexible exhaling pipe .e, a breathing valve chest 4) connected by a flexible pipe 6 and a branch pipe c with'the lower end of one or more 'air purifying cartridges or absorbers a. The upper ends of thelatter are in-communication with the valve chest by means of suitable flexible connecting" piping i whilea flexible inhaling pipe 2' leads from said valve chest 1) to the mouthpiece. The apparatus further includes an oxygen containing cylinder 2 having'a'closing member or stop valve .2 which lhe Ob ect of the inventlon is to produce.

andthrough the pipe a under reduced pressure into the said branchpipe 6 that is to say, into the air circulation of the apparatus. A breathin bag I) is" connected to the a flexible pipe 6 and a flexible by-pass conduit 0 (to be explained later on) extends between the oxygen supply pipe 03 and the supply pipe 7". A spring press-button valve mechanism p-is arranged at the reversing point of the said by-pass conduit, and a pressure gage g is mounted in connection. with the high pressure branch of the by-pass conduit, preferably close to the press-button valve so that the wearer of the apparatus may at any time easily look at the said gage and ascertain, when the oxygen in the cylinder 2 is. becoming exhausted.

The absorbers a, the branch pipe e and the oxygen cylinder 2 are mounted on and securely fastened by any suitable means, such as buckle straps f and pipe clips h, to a supporting plate 70 provided with shoulder straps s. The supporting plate labels a lati eral extension or arm n to the end of which is articulated the valve chest 22 preferably by means of a double hinge connection of well known construction, for example .said hinge connection may comprise a plate 0 having eyes or lugs at its longitudinal edges,'which lu'gs are pivoted by pins 22 and 0 to corresponding lugs of the arm n and the valve chesto (see Fig. 1 With this arrangement the chest 0 may yield under the influence of external forces and the-like and on both.

swing either on the hinge pin a or 0 or The supporting plate A; is provided at its sides with suitable leather straps q, q or the like serving as a waist-belt for holding the said supporting plate in position close upon the body of the wearer of the apparatus. The by-pass conduit 0 and the breathing bag I) may be suspended 'in any appropriate manner from the waist strap 9, so that after the wearer has put on the apparatus .the press-button valvep and the pressure gage g" are readily accessible and conveniently in view in front of the wearers body somewhat on the left hand side, whilst the breathing bag is located at the side of the wearer and extends across or around his hip in which position the bag does not hamper the movement of the leg.

Owing to the lateral position of the valve chest it is possible to lead the breathing pipes up under the arm of the wearer to the breathing organs and consequently in a position where the same are least inconvenient. The pivotal attachment of the chest 0 renders it possible to adjust the chest and breathing pipes in any desired or into the most convenient position with relation to the wearer. The lateral and pivotal arrangement obtained by means of the hinge connection admits of a compact construction of the valve chest, as well as providing ,for

convenient accessibility of the connecting orcoupling means of the air conducting pipes at the valve chest. Furthermore, after disconnecting the couplings of the said pipes and removing the hinge pins the valve chest may be readily and easily removed as a whole or self-contained part of the apparatus for cleaning, repairing or replacing. As the couplings -of the air conducting pipes at the valve chest are all in close proximity, they may, moreover, be covered by a common protecting leather apron wrapped around the valve chest in' any suitable manner not shown in the drawing.

As it isobvious from Figure 1, the ex- 1 haled air thecourse of which to the absorbers a is indicated by winged -arrows, traverses thesaid absorbers from below in an upward direction whilst the purified air the course ofwhich to the mouthpiece m is shown by ordinary or unwinged arrows, es-

capes at the top of the absorbers. Owing to this arrangement a better utilization and effect of the carbonic acid absorbing power of the chemicals (such as caustic soda, caus tic potash or the like) of the absorbers is obtained and at the same time the formation of moisture as well'as the 'agglomerating and clinkering (glazing) of the chemicals is reduced.-

' As shown in Figures" 2 and 3, the pipe or connection (Z which permits of the passage of high pressure oxygen from the oxygen cylinder .2 to the pressure reducing valve 1,

is provided at its side with a casing 9 in such fixture 27 having two some distance apart. The said two bores are in communication with each other by means of a small bore (1 so that oxygen from the cylinder 2 may pass directly into the easing 9 without passing through the pressure reducing valve 12' Practically the connectiond and the casing 9 are made in one single piece to form a sort of cross-piece constituting a self-contained structure capable of being mounted and dismountedas a unit and at the same time avoiding the necessity for high pressure packings between the said two parts (Z and 9. A stop-valve 10, 11 operated by a hand levet 12 controls the passage of the oxygen through the casing 9. Such stop-valves are well known and need'no'further description. In the operative position, the hand lever 12 is secured against unintentional turning by a suitable spring plate 13 attached to the casing of the pressure reducing valve 1' and embracing the said lever 12 with yielding pressure.

To the threadedend of the casing 9 (Fig. 7 is fastened, by means of a screw-cap 14, a nipple 15 into the central bore 14 of which is soldered or-otherwise secured a high pressure pipe 16 which is coiled like a spring pipe around a wire rope 17 which servesas a sup orting core. The end of said wire rope 1! is fastened in a suitable recess of a plug 18 whilst the high pressure'pipe 16 is passed through a central bore of this plug. The latter is hard soldered at 19 to the endface of the nipple 15 and moreover is provided with a second bore or passage 20 having an outlet nipple 21 the purpose of which will be explained later on. The high pressure pipe' '16 and its .core 17 extend around the body of the wearer about to the front of the latter and their front ends are fastened in a similar plug 22 (Fig. 6) having an eccentric bore or passage 23 the purpose of whiclr will be also explained later on. On the plug 22 which has a central bore 22 is screwed a nipple 24 (Fig. 5) the central bore 24* of whichis in line with the central bore 22", and on the nipple 24 1s screwed a casing 25. The latter at the same time forms a support for the high-pressure gage g to the interior of which a radial bore 26 extending from the central bore 24? of the nipple 24 is connected. On the free end of the nipple 24 which projects through the end wall of the casing 25, is screwed a lugs 28 between which is pivoted a bell crank lever 29, 29*, the downwardly directed arm 29? of said lever is provided with a'suitable pad 30 or the like adapted to close or shut off the outlet of the bore 24 under the pressure of the spring 31 acting against the horizontal arm 29 of the said bell crank lever.

The latter is no covered and protected against external influences by a sealed cap 32 screwed upon the threaded end of the casing 25. The bell crank lever 29, 29 may be operated to open the valve 30 by depressing a press button 1) which acts against'the lever arm 29 and the pressure of the spring 31 located in a recess 34 of the fixture 27. The press-button is supported by an elastic membrane 35 suitably suspended in an aperture 36 of the wall of the cap 32, said aperture being surrounded with a protecting rim or flange 32*. The interior of the cap 32 is in communication with the bore 23 of the plug 22 by way of a perforation I-l? in the bottom of the casing 25 and an eccentric bore 38 of the I nipple 24.

Over the high pressure pipe 16 and its supporting core 17 is pulled a flexible tube or hose 0 the ends of which are strapped or otherwise securely fastened to the plug 18 j and casing 25 respectively (Figs. (3 and 7). Vith this arrangen'ient a jacket 0 is formed practically around the pipe 16 and core 17, which jacket is in communication with the bores 23 and 20 of the two end plugs 22 and 18. The outlet nipple -21 of the bore 20 is connected by means of whose r (Figs. 7 and 1) with the reduced pressure oxygen supply pipe 1 For the purpose of admitting additional oxygen into the air passage of the apparatus as desired or required in the event of anincreased output of work on the part of the wearer of the apparatus, the wearer has but to exert a short finger-pressure upon the button p of the by-pass conduit and then to release it again. By this movement the lever29, 29 'is rocked and the valve pad 30 lifted away from the outlet of the bore 24 (Fig. 5),'so that a small jet of high pressure oxygen is permitted to pass from the supply pipe d'through the spiral pipe 16 and the connections ,above described into the cap 32-whereby it will be reduced in pressure at the same time. Thence the reduced pressure oxygen takes its course through the bores 37, 38' and 23 into and through the hose 0, through the bore 20, the outlet 21 and the hose 1' into the supply I piper and thence into the branch pipe e, that is to say,'into' the air passage of the apparatus. The supply of additional oxygen by means of the by-pass conduit into the circulating system of the apparatus independently of the pressure reducing mechanism r may be effected as often .as necessary by one or a plurality of successive pressure impulses on the button p.

It will be seen that under ordinarygvorka ing conditions the bell crank lever 29, 29* is under the pressure of its spring 31and the outlet 24* visclosed oi sealed" by, thevalve 30, so that high, pressure oxygenv can not enter into thereduced pressure oxygen reeie 3 turn branch of the by-pass conduit (Fig. 5).

The forward branch of the by-pass conduit being constantly 'in communication with the interior of the oxygen container 2, remains, however, filled up with high pressure oxygen, and as the pressure gage g is in constant comn'iunication with this forward branch, it will indicate the pressure or volume of the 'oxygen existing in the container at any time.

IV hen it is desired or required for any reason to cut oil the high pressure oxygen supply tothe by-pass conduit, this may be done by simply turning down the hand lever 12 (Figs. 1 and 2) and screwing home the valve screw plug 10 against the bore 9 (Fig. 3).

' I claim:

1. In a self-contained breathing apparatus of the kind described, the combination of a plurality of pipes, a fixture consisting of two integral sections extending trans-- versely to each other and provided with bores extending at approximately right angles to each other in different planes and each connected-with one ofsaid pipes, said fixture further having a connecting channel extending between said bores to connect the same, and a valve in said fixture for controlling the communication between said bores.

2. In a self-contained breathing apparatus of the kind described, the combination of an oxygen container, a high pressure valve, a pressurexgage, a fixture consisting of two, integral sections extending trans-' versely to each other in diiferent planes and provided with bores extending at approximately right angles to each other in said different planes, said fixture furtherhaving a connecting channel extending transversely between and connecting said bores, a valve' in said fixture for controlling the communication between, said bores, connections from one of said bores to said oxygen container and pressure-reducing valve respectively, and a connection from the other bore to said pressure gage.

3.-In a self-contained breathing apparatus, the combination of means for providing respirable air, a pressure-reducing valve connected with said means, a container for high pressure oxygen connected with said pressure-reducing valve, a bypass conduit for said pressure-reducing valve, a pressure gage in continuous connection with said by pass conduit, a cap extending over said bypass conduit, a bell-crank lever mounted within said cap,'a valve carried by said lever and controlling said by-pass conduit and a press-button for actuating said lever to operate said valve.

4. In a self-contained breathing apparatus, the con'ibina'tion of means for providing respirable air, a pressure-reducing valve connected'with said means, acontainer for high pressure oxygen connected with said pressure-reducing valve, a by-pass tube connected with said means independently of said pressure-reducing valve, a fixture connected with the free end of said tube, a high pressure pipe connected with said oxygen container and extending lengthwise through saidtube into connection with said fixture, a valve-seated bore in said fixture communieating with said high pressure pipe, an eccentric boi'e in said fixture communicating with said tube, a pressure gage carried by said fixture in constant communication with said high pressure pipe, a cap connected with said fixture, a bell-crank lever within said cap, a valve carried by said lever and co-ope'rating with said valve seat to control the communication between the two bores and between the high pressure pipe and said by-pass tube, and a press-button mounted on said cap for. actuating said bell-crank lever to operate said valve. 7

5. In a self-contained breathing apparatus, the combination of means for providing respirable air, a pressure-reducing valve connected with said means, a container for high pressure oxygen connected with said pressure neducing valve, a by-pass tube connected with said means independently of said pressure-reducing valve, a fixture con- 30 nected with the free end of said tube, a wire-supporting rope extending through said tube and connected with said fixture, a high pressure pipe connected with said oxygen container and coiled about said rope, 35

lengthwise of said tube into connection with said fixture, a valve-seated bore in said fixture communicating with said high pressure pipe, an eccentric bore in said fixture communicating with said tube, a pressure gage 4 carried by said, fixture in constant communication with said high pressure pipe. a cap connected with said fixture, a bell-crank lever within said cap, a valve carried by said lever and co-operating with said valve seat 45 ALEXANDER BERNHARD DRAGER. 

